Considered a single stock: A group of individuals in a species occupying a well defined spatial range independent of other stocks of the same species. It can be affected by random dispersal movements and directed migrations due to seasonal or reproductive activity.

Spatial Scale: Spatial scale contains a standard term such as Global, Regional (e.g. for the whole Atlantic), sub-regional (e.g. for a part of the Atlantic), national, local (for sub-national levels).

Considered a management unit: An aquatic resource or fishery is declared as [Fishery] Management Unit if it is effectively the focus for the application of selected management methods and measures, within the broader framework of a management system. According to the FAO Glossary for Responsible Fishing, "a Fishery Management Unit (FMU) is a fishery or a portion of a fishery identified in a Fishery Management Plan (FMP) relevant to the FMP's management objectives." FMU's may be organised around fisheries biological, geographic, economic, technical, social or ecological dimensions , and the makeup and attribute of a fishery management unit depends mainly on the FMP's management objectives.

UWTV survey estimates are available for 1993–1994 and from 1996 onwards. Length compositions from the commercial fishery are available from 1980. Potential bias in survey design has been detected and accounted for in the assessment this year (see “Data and methods” section at the start of section 6.4.14.)

Uncertainties in assessment and forecast

General comments are found at the start of section 6.4.14

Information from the fishing industry

The NSCFP survey (Figure 6.4.14.3) does not include specific information for the Moray Firth.

Comparison with previous assessment and advice

The perception of the stock in 2008 is similar to that of the stock in 2007

The advice in 2008 was based on recent landings as the UWTV surveys were considered inappropriate to use as absolute indices of abundance. Following the outcome of the benchmark in 2009, the major concerns of the UWTV survey have been addressed and the survey is now considered a reliable estimate of absolute abundance.

The landings forecast for 2010 (< 1 372 t) is considerably lower than for 2009 (< 1 800t). This is due to using the status quo F (F2008) as the target F for this stock in the current advice.

ICES advises on the basis of exploitation boundaries in relation to high long term yield and low risk of depletion of production potential that the Harvest Rate for Nephrops fisheries should not exceed F2008. This corresponds to landings of no more than 1 372 tonnes for the Moray Firth stock.

1) Does not include discards. 2) It is not advised to manage these stocks as a single unit.

Management

Management unit: Yes

Management Advice

Management considerations

To protect the stock in this Functional Unit, management is required to be implemented at the Functional Unit level.

A reduction of the catch corresponding to F2008 can be considered as an intermediate step toward F0.1 (as a proxy for Fmsy). Alternatively, a constraint on the year to year change in TAC as is typical of management plans and the Communication on Fishing Opportunities for 2010 [COM (2009) 224] might be considered.

There is a bycatch of other species in the Moray Firth area. It is important that efforts are made to ensure that unwanted bycatch is kept to a minimum in this fishery. Current efforts to reduce discards and unwanted bycatches of cod under the Scottish Conservation credits scheme, include the implementation of larger meshed square mesh panels and real time closures to avoid cod.

Factors affecting the fisheries and the stock

In the Moray Firth area the Nephrops stock inhabits a single continuous area of muddy sediment extending from north of Fraserburgh to Inverness.

The Moray Firth Nephrops ground is located close to the Scottish coast and is exploited almost exclusively by UK vessels. Landings from this fishery are predominantly reported from Scotland, with very small contributions from England in the mid-1990s, but none recently.

Regulations and their effects

Discarding rates averaged over the period 2006 to 2008 for this stock were about 6% by number. This represents a marked reduction in discarding rate compared to the average for the period 2003 to 2005. This may arise from the increasing use of larger size meshes in the northern North Sea, although reduction in recruitment may also account for this change.

Biological State and Trend

State & Trend Descriptors

Partner

FIRMS

Exploitation rate

Undefined

Uncertain/Not assessed

Abundance level

Undefined

Uncertain/Not assessed

The evidence from the UWTV survey suggests that the population is stable, but at a lower level than that evident from 2003-2005. The UWTV survey information, taken together with information showing stable mean sizes, suggest that the stock is being exploited sustainably.